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Electromagnetic Induction Physics Ncert Solutions Class 12th Physics Class 12th Physics NCERT Exemplar Solutions Class 12th Chapter Six

A cylindrical bar magnet is Rotated about its axis. A wire is connected from the axis and is made to touch the cylindrical surface through a contact. Then,

(a) A direct current flows in the ammeter A

(b) No current flows through the ammeter A

(c) An alternating sinusoidal current flows through the ammeter A with a time period 2π/ω

(d) A time varying non-sinusoidal current flows through the ammeter A

5 Views | Posted 4 months ago

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Answered by

Payal Gupta | Contributor-Level 10

4 months ago

This is a multiple choice answer as classified in NCERT Exemplar

(b) When cylindrical bar magnet is rotated about its axis, no change in flux linked with the circuit takes place, consequently no emf induces and hence, no current flows through the ammeter A.

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An aeroplane, with its wings spread 10m, is flying at a speed of 180 km/h in a horizontal direction. The total intensity of earth’s field at that part is 2.5 × 10^-⁴Wb/m² and the angle of dip is 60°. The emf induced between the tips of the plane wings will be…………..

alok kumar singh

B_v = B sin 60°

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(A) The magnet's entry

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